ConnectyleMen's Foldable Sports Sun Hat Runner Cap Baseball

Q: Why does it fold? What’s the purpose?

It fits in your pocket or backpack when folded. I use it when riding my motorcycle so my hat is handy when I take off my helmet.

Q: How much "longer" is the bill compared to a regular cap bill?

It is 1-2" longer than other baseball caps I have, enough to make it look weird to me. I am returning mine because I think it looks goofy on me due to the long bill. Too bad, because otherwise the gray one I got would have been a very comfortable cap that would have gone with everything.